Improvement in apparatus for distilling oils



l. HOWARTH.

Oil Still.

No. 20,562. Patented June 15,1858.

N. PETERS. Phvlo-Lxlhogrnplm, vla-hingen", D. C.

4UNTTEE STATES PATENT OFFICE.

JOHN HOVARTH, OF SALEM, MASSAOHUSE'IVIS.l

IMPROVEMENT IN APPARATUS FOR DISTILLING OILS.

Specification forming part of Letters Patent N0. 20,562, dated .lune15,1858.

To @ZZ whom, it may concern:

Be it known that I, JOHN HoWAR'rH, of Salem, in the county of Essex andState of Massachusetts, have invented certain new and usefulImprovements in Apparatus Used for Distilling Bosin-Oil and other Oils;and I do hereby declare that the following description, taken inconnection with the accompanying drawings, hereinafter referred to,forms a full and exact specification of the same, wherein I have setforth the nature and principles of my said improvements, by which myinvention may be distinguished from others of a similar class, togetherwith such parts as I claim and desire to have secured to me by LettersPat-- ent.

rlhe iigures of the accompanying plates of drawings represent myimprovements. Figure l, Plate 1, is a plan or top View ofA my improvedapparatus. Fig. 2 is a central vertical section of the same. Fig. 3,Plate 2, is a front elevation.

Before proceeding to describe in detail the features of my invention, Iwill rst state the process commonly employed in the distillation ofrosin-oil, in order that the distinctive features of myimprovements maybe clearly manifested and more readily understood.

By the usual .mode of producing rosinoil the products of distillationconsist of water, naphtha, and afterward oil of different degrees ofthickness and quality, the oil which comes over at a certain stage ofthe distillation .being of the best quality, while that which followsbecomes thicker and thicker as the process goes on until the contents ofthe still are exhausted with the exception of the residue,

which consists of pitch. The still is then allowed to cool byextinguishing the fire, the pitch removed, the still recharged withrosin, and the heating process recommenced. This, it may beremarked, isa daily operation, the still being replenished with rosin once intwenty-,four hours.

The disadvantages ofthe above process may be briefly enumerated asfollows: a great waste of fuel, as from four to tive hours of heatingare required before the evaporation commences, while the frequentchanges of temperature of the still in consequence of its repeatedheatings and coolings renders it liable to crack and break second, theoil left on the hot sides of the still as it is boiled down, especiallyon that portion of the surface that comes in contact with the flues,that extend two or three times around the still, becomes carbonized, andthereby discolors the oil and injures its quality. The Want ofuniformity in the results of the distillation, on account of theimpossibility of keeping up a uniform temperature in the still, as thevapors are made faster when the oil gets lower in the still, and areliable to be carbonized unless the rire is regulated with great nicety.

The most essential feature of my improve- :ments consists in introducingheated oil under pressure into the still in such a manner as to keep upa constant feed and retain the oil always at one and the same level.From the statement hereinbefore made that at one stage of thedistillation, when the oil is brought down to a certain point in thestill, oil of the best quality is produced, the importance oithuskeeping up a constant supply of heated oil, so as to retain thedistillation always at that stage when the best quality of oil is made,will be apparent, as the result is invariably and necessarily oil of thefirst class, and that only, and not, as in the old process, oils of allthe different grades in one distillation from the thinnest and best tothe thickest and poorest, until the last production is nothing butpitch. By this improvement the distillation can be kept up for anylength of time without stopping to cool, and then recharge the stillevery twenty-four hours, as no pitch can be formed until the feeding-inof the oil is stopped, while a large percentage of fuel is saved, as itis only necessaryto keep the still always at one temperature, instead ofreheating a cold still every twenty-four hours, and it is requisite onlyto regulate the fire so as to keep the oil at a certain degree of heat,in-

,stead of varying the temperature of the oil according to its height inthe still, as heretoforean operation requiring great skill and care onthe part of the attendant. The carbonization of the thin strata of oilremaining on the sides of the still in contact with the iiues, whichnecessarily occurs by the old pro cess, is also prevented by myimprovements, as the inner surface of the still is kept protected by theconstant feed of oil, which is thereby maintained at a sufficient'height to cover and extend above the surface exposed to the heat of theflucs.

I have also made several other improvements, which will be hereinafterreferred to and fully explained.

a a a in the drawings represent the supporting masonry of the-distillingapparatus. I) b is the fire-chamber communicating with flues c and d,formed in the brick-work, and extending around the still e c in theusual manner. f is a reservoir or receptacle to contain the oil ormelted rosin with which the still is to be charged. This reservoir f isplaced above the top of the still, in order to induce the necessarypressure upon the oil. A pipe, g g, conducts from it and delivers theoil into a funnel, h. This funnel h is placed at the same height atwhich the oil is to be kept in the still, and has its supply regulatedby a stopcock, z', in the pipe g g. The oil received by the funnel hpasses down through a pipe, k, which communicates with a worm, Z,inclosed by a cylinder, m, into which steam is admitted, so as tosurround the worm and heat the oiltherein. 'Ihe oil thus heated isforced from the worm through the pipes n and o into the still, near itsbottom.

From the above description it will be seenthat the still is constantlyfed with heated oil under pressure, and, furthermore, that the oil willbe always kept at the same level in the still as the height of thefunnel h, the supply to which is regulated by the stop-cock i in thepipe g, so as to keep it full, or nearly so, and thereby feed in the oilto the still as fast as it is wanted and no faster, so as to preserve auniform level, the objects and advantages'of which have hereiubeforebeen fully stated.

The importance of feeding in heated instead of cold oil will beapparent, as it is vitally essential to the success of the process thatthe temperature of the oil should always be kept the same, and as thetemperature is usually about 450 to 550o Fahrenheit, the feeding in ofcold oil would, it is evident, lower the temperature at once.

By the usual arrangei'nent 0f rosin-oil apparatus, the oil or rosin, asthe case may be, is put into the still through a man-hole77 formed inits top, and when the still is charged the distillation is commenced. Bymy improvement it will be seen that a constant feed is kept up, thewhole process forming a continuous operation.

p p is the condenser, placed upon the top of the still and within atank, qq, in such a mannor as to expose the whole of its surface to coldwater which is supplied to the water-tank by means of a force-pump. Asthe hot vapors rise from the oil in the still they will strike againstthe cold surfaces of the condenser and become condensed thereon, and rundown the same to the bottom s s of the condenser, thence through theelbow-pipe t t into a second condenser, a u, where whatever vapors thatmay remain are condensed, the condensing-water being supplied by a pipe,o, upon the tank q q.

I will next proceed to describe my improvement for increasing theeffective operation of the condensing portion of the apparatus. Vith thevapors that rise into the condenser fromthe still arelarge quantities ofcarburetedhydrogen gas and other incondensable gases, which rise to thetop of the condenser and prevent rapid condensation of the vapors, bothby occupying condensing-space and by pressure,which it is essential toavoid, as, if the vapors be not rapidly condensed, they will becomecarbonized in the still. I have provided means for relieving theincondensable gases from the top of the condenser by means of a pipe, ww, having openings or communications :u x, Ste., with thecondensing-spaces g/ y, into which the vapors rise. The pipe w wconducts off the gases by a pipe, j, into the second condenser, u u, incompany with the oil received from the pipe t t at the bottom ofthecondenser. After thus passing through the second condenser, u a, theuncondensed gases will escape through the long gas pipe or flue j,andthe oil will be delivered through a short pipe, z.

Vere it not for the arrangement above described, the carbureted-hydrogengas could not be prevented from occupying nearly the whole space in thefirst condenser, as there would be no outlet except at the bottom, oilvapors and gases having to pass out at that point. By my improvement thegases find a free exit through the top of the condenser, while the oilcondensed can find its way out at the bottom pipe, tt.

The next improvement which I shall describe relates tothe bleaching ofthe oil or removing watery particles from it. The bleaching hasheretofore been an independent operation, the oil, after being deliveredfrom the still, being heated sufficiently to expel the watery vapors inlarge open vessels. rIhis mode of bleaching allowed the heated oil tocome in contact with the atmospheric air and to absorb the oxygen of thesame, which absorption of oxygen invariably discolored the oil,rendering it much darker than before the operation.

My improvement consists in conducting the oil, after it has passedthrough the second condenser, through a heated worm or coil of pipesprotected by a covering of clay, whereby the oil is bleached as fast asit is run through the still and without coming in contact with the air.The oil is delivered from the second condenser, a u, through a shortpipe, z, into a funnel, a', which is placed upon the top of andcommunicates with a worm or series of bent pipes, b b. These pipes b bare covered with clay or other suitable material, and set in a furnace,c c, that forms a part of or may be connected to the brick-work d a ofthe still.

By protecting the pipes b b with a coating of clay, the oil passingthrough the said pipes is prevented from being overheated, the coveringof clay serving to protect the pipes from the action of the fire, andalso, which is very important, during the bleaching operation preventingsudden changes of temperature in the oil. After thus being passedthrough the heated pipes b b and bleached Without being exposed to theair, the oil is delivered through an elboW-pipe, d.

The last improvement I have made consists in preventing the pitch thatmay adhere to the side of the heated still from passing into and throughthe condenser and becoming incorporated with the oil, which materiallyinjures its color and quality. I eiiect this desideratum by forming inthe neck e e of the still and communicating therewith a deep circularglitter, ff, Fig. 2, which receives all Having thus described myimprovements, I shall state my claims as follows:

1. In combination with the still, the reservoir, placed above the levelat which the oil is to be kept in the still, and the Worm, heated asdescribed or in anyother manner, whereby heated oil nnder pressure isfed into the still in such a manner as to keep the oil therein always atone and the same level, as set forth.

2. The use of a pipe communicating with the several vapor-spaces Withinthe still, as described, whereby the condenser is relieved from theincondensable gases that are generated in the still, and which preventthe effective condensation of the vapors.

3. A gutter formed in the neck of the still, for the purpose specified.

t JOHN HOVVARTH.

Witnesses:

Josnrn: GAvE'rT, ALBERT W. BROWN.

